, i remember seeing that now, that you shouldn't apply until 28 days before the spousal visa expires.
We need to be careful these days, given spouse visas issued outside the UK, on or after 22 July 2008, should be for 27 months rather than 2 years.
It is safer to say that the ILR application can be made no earlier than 28 days before the 2nd anniversary of the first date of arrival using that spouse visa.
The point is that someone issued with a 27 month visa, who flies to the UK reasonably promptly, can apply for their ILR well before the last 28 days of validity of their visa.
And for someone with a 2 year visa, issued prior to 22 July 2008, the application should be made no earlier than 28 days before the 2nd anniversary of them first arriving .... not 28 days before the expiry date of the visa. Accordingly, if someone arrived say 10 days after the start of the 2 year visa, they have an 18 days "window of opportunity" to submit the ILR application, not 28 days.